Question: Who gave the{birthdate} of {doctoral student} of {Martin Luther} ?
Paraphrase: Who gave the{birthdate} of {doctoral understudy} of {Martin Luther} ?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q9554 wdt:P185 ?X . ?X wdt:P569 ?answer}
Answer: 1509-01-01T00:00:00Z